tailieunhanh - Báo cáo khoa học: Promoters of type I interferon genes from Atlantic salmon contain two main regulatory regions

Recognition of viral nucleic acids by vertebrate host cells results in the syn-thesis and secretion of type I interferons (IFN-a⁄b), which induce an anti-viral state in neighboring cells. We have cloned the genes and promoters of two type I IFNs from Atlantic salmon. Both genes have the potential to encode IFN transcripts with either a short or a long 5¢-untranslated region, apparently controlled by two distinct promoter regions, PR-I and PR-II, respectively. | ỊFEBS Journal Promoters of type I interferon genes from Atlantic salmon contain two main regulatory regions Veronica Bergan Silje Steinsvik Hao Xu 0yvind Kileng and B0rre Robertsen Department of Marine Biotechnology Norwegian College of Fishery Science University of Tromso Norway Keywords Atlantic salmon interferon promoter interferon regulatory factor nuclear factor kappa B NFkB poly I C Correspondence B. Robertsen Department of Marine Biotechnology Norwegian College of Fishery Science University of Tromso N-9037 Tromso Norway Fax 47 776 45110 Tel 47 776 44487 E-mail Received 24 April2006 revised 9 June 2006 accepted 15 June 2006 doi Recognition of viral nucleic acids by vertebrate host cells results in the synthesis and secretion of type I interferons IFN-a b which induce an antiviral state in neighboring cells. We have cloned the genes and promoters of two type I IFNs from Atlantic salmon. Both genes have the potential to encode IFN transcripts with either a short or a long 5 -untranslated region apparently controlled by two distinct promoter regions PR-I and PR-II respectively. PR-I is located within 116 nucleotides upstream of the short transcript and contains a TATA-box two interferon regulatory factor IRF -binding motifs and a putative nuclear factor kappa B NFkB -bind-ing motif. PR-II is located 469-677 nucleotides upstream of the short transcript and contains three or four IRF-binding motifs and a putative ATF-2 c-Jun element. Complete and truncated versions of the promoters were cloned in front of a luciferase reporter gene and analyzed for promoter activity in salmonid cells. Constructs containing PR-I were highly induced after treatment with the dsRNA poly I C and promoter activity appeared to be dependent on NFkB. In contrast constructs containing exclusively PR-II showed poor poly I C -inducible activity. PR-I is thus the main control region for IFN-a b synthesis in salmon. Two pathogenic RNA